ORA-23404 refresh group does not exist

ORA-23404 refresh group does not exist
Cause: A refresh group name was given that is not in SYS.RGROUP$.
Action: Provide a refresh group name that is in SYS.RGROUP$ or DBS_RGROUP.

Reference: Oracle Documentation

Example:

Today I faced this error on my DB, as I was trying to refresh a MVIEW using DBMS_REFRESH.REFRESH
 - EXEC DBMS_REFRESH.REFRESH('MYMVIEW');
But when I explorered and find DBMS_REFRESH.REFRESH refreshes a refresh group.

So I canged my statemanet to 
 - EXEC DBMS_MVIEW.REFRESH('MYMVIEW');
and it worked !!!

Another way is to make a Refresh Group first and then Refresh it using DBMS_REFRESH.REFRESH as
 - EXEC DBMS_REFRESH.MAKE(NAME=>'MY_GRP', LIST=>'MYMVIEW', NEXT_DATE => SYSDATE, INTERVAL => 'NULL');
 - EXEC DBMS_REFRESH.REFRESH('MY_GRP');